The invention offers many applications, in particular trajectory determination for tracking moving targets.
The invention in particular relates to the field of remotely-piloted flying motorized apparatuses, also called drones (or UAV, Unmanned Aerial Vehicles), in particular dedicated to land or maritime surveillance. The invention is then particularly useful to optimize guiding of the drone when the drone is in a tracking mode to track a given target moving on the ground or over water.
To track land or maritime moving targets, an existing solution consists of implementing remote piloting of the aerial drone by an operator on the ground to track a moving target. However, this solution is limited by the range of the link between the drone and the operator, this range limiting the movement autonomy of the drone relative to the operator on the ground controlling it.
To resolve this, autonomous solutions for automating target tracking have been developed, which include the so-called tangent method described in the article “Autonomous Target Following by Unmanned Aerial Vehicles” by Rafi et al., based on the autonomous (i.e., without any operator intervention) determination by the drone of a trajectory comprising a series of circles respectively centered on successive positions of the moving target. This technique is also based on slaving to the current “drone-target” distance, the current “drone-target” distance being measured in a plane (2D), horizontal relative to the surface of the ground, the plane comprising both the point representative of the current position of the target and the projection in this plane of the point representative of the current position of the drone.
However, none of the solutions proposed to date are fully satisfactory, in particular in terms of continuous visibility of the target and in terms of trajectory optimization, such that the entire trajectory is “flyable” by the drone.